Enlarging or reducing photographic printer



April 1--, 1924. 1,488,846

A. M. THOMAS ENLARGING OR REDUCING rno'roennmc PRINTER Filed 058,18. 1922 ,2 Sheets-Sheet 1 April 1 1924. 1,488,846

A. M. THOMAS ENLARGING 0R REDUCING PHOTOGRAPHIC PRINTER Filed Oct. 16 1922 2 Sheets-Sheet 2 i ii .;L.-,;.l.-------:--- 221k fig 48 3215" W Patented Apr. 1, 1924.

UNITED STATES 1,488,846 PATENT OFFICE,

ALFRED I. THOIAS, I031 I030, COLORADO.

ENLARG ING OB BEDUCING PHOTOGRAIHIO rm'mn.

Application ma 0mm 18, ms. semi Io. 594,888.

the following is a specificatiomreference being had to the accompanying drawings.

This invention relates to machines for printing photographs, and particularly to those machines in which the image to be printed is enlarged or reduced with relation to the size of the original negative.

Machines of thi character embody ordinarily a table upon which the sensitized paper is disposed, a source of illumination, a lens which is disposed between the table and the source of illumination, and a negative carrier disposed between the source of illumination and the lens. In the greater number of enlarging photographic projectors of this character the lens ha to be focused by hand as well as adjusted for producing the desired enlargement or reduction.

The general object of my invention is to provide means for automatically focusing the lens as the negative and lens are move toward or from the table upon which the sensitized paper is disclosed. I

A further object i to provide manually operable means whereby very finefocusing adjustments may be made or the lens shifted sli htly out of focus if desired.

still further object is to provide means whereby the apparatus is adapted to. produce prints reduced with relation to the original negative.

Still another ob'ect is to provide an automatic focusing evice of this character which is very simple, which cannot readily get out of order, and in which a relatively wide range of focusing movement is provided for.

Other objects have todo with the details of construction and'arrangement of parts as will appear more fully hereinafter.

My invention is illustrated in the accompanying drawings, wherein Figure 1 is aside elevation partly broken away of my improved photographic print-- in" machine;

igure 2 is a fragmentary front elevation, the lamp hood or lantern being in section;

Figure 3 is an enlarged front elevation of the automatic focusing mechanism, the negative support, the lamp hood and the bellows being removed;

Figure 4 is a section on the. line 4-4 of F1 re 3;

lgure 5 1s a section on the line 55 of Fi re 3 i gure 6 isa fragmentary longitudinal section on the line 6-6 of Figure 3;

Figure 7 is a fra entary vertical-section on the line 7-7 of igure 2;

Figure 8 is an enlarged sectional view through the clamping members 78 and 79.

Referring to these drawings, 10 designates a base upon which is erected an upright or column section 11, which at its upper end is provided with an upwardly projecting pin 12. Mounted upon the upright 11 is the cross pica) 13, which by means of a bracket 14 supports a transverse beam 15. Hinged to this transverse beam 15 is the table 16,

which may be of any suitable form or con- Detachably mounted upon the upright 11 is a column, which is designated generally 20. This column is formed. of a medially disposed beam or'member 21, to which, as illustrated in Figures 1 and 5, there is attached a metallic clip 22 formed at its rear end with an eye 23 embracing the pin 12. At its lower end the member 21 is formed with a socket 524, as illustrated in Figure 7, and extending upward through the member 13 andthrough the member 15 is a pin 25 which engages in said socket, there being an angle iron 26 connecting the members 13 and 15 through which this pin 25 passes. Thus the "column 20 is vertically movable with relation to the upright 11 and is also detachable from the upright 11. The column 20 weight compartment 29. These members may be connected to each other in any suitable manner.

posed casing members 28 which extend beyond the -members 27 so as to form a The upper end of the column is formed by a member 30 carryin the grooved wheels or pulleys 31, over whic passes a cable 32, one end of this cable being connected to acounterweight 33 moving within the weight compartment 29. The opposite end of this cable 32 is connected to the slide, designated generall 34, this slide being formed of a rear mem r 35 and two guides 36 attached to the front of the member 35 are spaced from each other. Attached to the member 35 are inwardly projecting guides 37 which move in the space between the upright 21 and the side pieces 28 and are guided thereby. Metal facing stri 39 are disposed upon the outer faces 0 the upright 21 and the side pieces 28. As illustrated in Figure ,4, the members 37 are attached to the guides 36 by angular metallic strips 40 which are attached to the inside faces of the members 36 and which extend inward on each side of the u right 21 and are attached to the guides 37. ne of these strips extends inward nearly to the members 27 and is attached to a slide 41 operating between the adjacent member 27 and the guide strip 42. Thus it will be obvious that the slide 34 may move up and down the full length of the column.

Mounted in the space between the members 36 is a slide 43. This slide is held in place between the members 36 by means of the strips 44 attached to the member 36 and extending over the margins of the slide 43. The upper end of the slide 34 is attached to the cable 32 in any suitable manner. The slide 43 which carries the lens is shifted with relation to the slide 34 which carries the hood and the negative holder by means of two levers 45 which are pivoted at 46 upon transverse metallic strips 47 mounted upon the faces of the members 36. These two levers 45 cross each other at their lower ends and their inner edge faces are given a certain curvature to exert a camming action upon rollers 48 mounted upon the outer extremities of a T-sha (1 member 49 which is pivoted to the face of slide 43, as at 50. The T-shaped member 49 is laterall shiftable upon its pivot 50 and the ro lers 48 contact with the inner slightly curved faces of the levers 45 so that as the outer ends of the levers are depressed the inner ends will move toward each other and will exert a lifting force upon the rollers 38 and upon the slide 43. and that reversely as the upper ends of the levers 45 move toward each other the lower ends below the pivot points 46 will expand and permit the rollers 48 to move down and the slide 43 to move down. This movement of the levers .45 is secured b links 51 which are pivoted to the upper en s of levers 45 and extend upward convergently and are pivoted to an outwardly and laterallly projecting bracket 52 which is attached to the member 21 in any suitable -manner, this bracket 52, as illustrated in Figure 1, projecting outwardly and then laterally so as to provide a space for the cable 32.

Below the intersecting ends of the levers 45 the slide 36 has an outwardly projecting, longitudinally extendin guide 53 and on each side of the guide t e slide 43 has the angularly disposed guide strips 54. Disposed on each side of the guide rib 53 are the plates or metallic strips 55 whose inner ends are an 'ularly bent to engage beneath the guide flanges 54. These strips or plates 55 extend out beyond the guide rib 53, and disposed between the outer ends of these strips is a filler block 56,-the strips or plates 55 being attached to this filler block by transversely extending screws, bolts or other like devices 57. The plates may be contracted upon the guide rib 53 or expanded with relation thereto so as to increase or decrease the frictional engagement of the strips 55 with the guide rib 53 by means of the transversely extending bolt 58 to which a wing nut 59 is attached. The outer ends of the strips or plates 55 are angularly bent away from each other and then extended outward to partially embrace a lens support 60 carrying the lens 61 therein.

It will be seen that the member 55 is thus lon itudinally shiftable with relation to the sli e 43 and that this slide 43 in turn is longitudinally shiftable with relation to the slide 34. The lens carrier 60 is vertically adjustable by means of a hand lever 62 which is pivoted at one end to :1. lug 63 projecting downward from the lower end of the slide 43, this lever being connected by a link 64 to one of the sliding plates 55. These sliding plates have frictional engagement with the tongue or rib 53 so that the lens carrier will be frictionally held in any adjusted position and by shifting the lever 62 upward or downward, the lens carrier may be shifted through a slight range The frame 65 is formed with air inlet ports 72 which are angular so as to prevent the light from escaping from the frame but permit the inlet of air. The lower portion of the frame 65 is attached to a bellows 73 whose lower end in turn is connected to the lens box or support 60. The frame 65 is sensitized sheet sup orted thereby.

formed with an opening for theinsertion of a negative carrier 74 of an suitable construction which is, of course, isposed below the lamps 68 and which has a handle 75 whereby it may be readily inserted into the frame 65 or removed therefrom.

It will be obvious now that with this construction automatic means is provided for accurately focusing the projected image of the negative onto the table 16 and onto the When it is desired to ma e an enlargement the slide 34'is shifted by hand upor down its guideways on the column 20 so that the pro r sized image is projected upon the tab e 16. The further away the lens61 is from the table, the larger .will be the enlar ement, and the nearer this lens 21 to the tab e, the smaller will be the enlargement. As the slide 34 moves downward the levers 45 will move toward each other at their upper ends and thus permit the T-shaped member 49 to descend. This permits, of course, the descent of the slide 43 relative to the slide 34. thus expanding the bellows and correctly focusing the lens 61 upon the table. As the slide 34 is moved upward, however, the upper ends of the levers 45 will be caused to move away from each other by the links 51 so that the inner edges of the lower ends of these levers will lift up on the rollers 48, thus lifting the slide 43 with reference to the slide 34 and compressing the bellows. Thus the focusing of the lens 61 is absolutely automatic and it 18 only necessary for the operator to shift the slide 34 to a position where the correct enlargement will be had in order to secure the accurate focusing of the lens.

In some cases the photographer or printer places the negative in the negative holder with the film side downward and in other cases with the film side upward, and this requires a slight difference in focusing. This is provided for by shifting the lens carrying slide relative to the slide 43 a sllght amount by means of the lever 62. This lever 62 may also be used where the sensitized paper is not disposed upon the table 16 but is put in a frame, making a slight difference in elevation. It may be also used for throwing lens 61 slightly out of focus in case it is desired to soften the image.

One of the principal features of this invention is the provision of means whereby reductions may be made as well as enlargements, and in order to make a reduction it is necessary to increase the distance between the late and the table 16 over that ordinari used for producing enlargements, and it is i or this purpose that I have so mounted the column 20 upon the supporting frame that the column 20 may be lifted a redetermined amount and held in its lift osition whenever desired. To this end I ave mounted upon the member 15 a vertical iron 76 havin a plurality of a ertures 77, this member 76 being in space relation to the confronting face of the column, and I have formed the lower end of the vertical member 21 with one or more apertures adapted to register with the apertures 77 so that a screw-driver or other tool may be inserted through one of the apertures 77, engaged with an aperture in the face of the beam 21, then the tool will be pressed so as to raise the column.

In order'to hold the column raised relative to the table 16, I attach to the member 15 in one side a U-shaped guide 78, and

ivot within this guide a clamping member 9 having an aperture through which a rod 80 passes, this rod being ivoted upon a bracket 81 attached to t e member 21. When this clamping member 79 is at right angles to the rod 80 it will permit the rod 80 to be raised or lowered, but when at less than a right angle it will bind upon the rod 80 and hold this rod from downward movement. Thus it will be seen that the column may be'raised any necessary amount by the tool inserted through the apertures 77 and that then when the column is released the rod 80 will be engaged by the clamp 7 9 and the column held in a raised position. When it is desired to release the column, the clamping member 79 is to be shifted toa position at right angles to the rod 80 and the tool used to lower the column relativeto the table 16. As before remarked, this adjustment ermits of reductions being made, which re uctions are impossible with any other printing machine known to me, which printing machine is capable of making enlargements.

I have found in actual practice that it is particularly desirable to use a plurality of lamps 68 in place of the one lamp generally used, as this distributes the heat over the V face of the negative. If one lamp was used of sufficient candlepower to give the requisite illumination, the heat given off by this lamp would be so eat that there would be liability of crac ing the negative or otherwise injuring it, 'as this heat would be concentrated at one oint on the negative. By providing a p urality of lamps, however, this concentration of heat upon the negative is prevented. These lamps, however, would tend tocrack the negative orotherwisein- 1 jure it were itnot for the fact that there is a constant indraft of cool air through the apertures 72, this cool air passing upward and being drawn out by the exhaust fan 70. The

cool airis admitted through the apertures.

72 immediately above the negative holder 7 4 and all the heat is carried away from the negative, thus preventing any cracking or other injury to the negative. I have found in actual practice that a much more efiec-' tive result is secured by exhausting the air iii column to be raised and lowered without permitting the column to tip with reference to the base or to be dislodged from the base unless it is desired to entirely remove the column from the base for transportation or for packing. The arms 45 may be longer if desired or shorter without departing from the spirit of the invention, but any lengthening or shortening of the arms will require that a different curvature be given to the inner edge faces of these arms than that illustrated in the drawings. By making the arms relatively long and decreasing the curvature of these edge faces, the range of movement of the slot 43 may be correspondingly increased. It is, of course, obvious that the arms, when the upper ends are shifted to their minimum distance from each other, must at all times prevent the complete descent or too great descent of the slide 43. The member 49 which supports the rollers 48 is preferably pivoted at 50 in order to permit this member to shift laterally and compensate for any minute irregularities in the inner edge faces of the arms 45. This member 49, therefore, acts as an evener and both rollers 48 will at all times engage the inner edge faces of the adjustin levers 45.

he action of the levers 45 is such that a very rapid increase in the ratio of movement of the lens relative to the negative is secured as the slide 36 moves downward. My construction secures a very wide range of movement of this slide, so that the slide may be moved down beyond the point where an image is printed on the sensitized paper of the same size as the negative and thus considerably reduced prints may be secured. In making enlargements it is necessary that the slide 36 be shifted downward until the image of the negative has been reduced to the extent required. At this point, however, the image while of the size required,

' thatis of the reduction required, will not be well defined and will be out of focus and it is necessary in order to secure proper definition that the negative shall be raised to a greater or less degree until this focus is se-' cured. It is for this purpose that I have "provided the means illustrated in Figure whereby the column as a whole may be raised with reference to the table so as to raise the negative holder with relation to the table. This does not affect the lens, as the lens when it is relatively close to the paper requires considerable movement in order to in any way affect the image.

I do not wish tobe limited to the particular means illustrated for relatively shifting the negative carrier and the table, as 0t 1651 means might be used for this purpose without departing from the spirit of the invention, but I have particularly devised this means for the reason that it is simple, the column with the negative holder and other arts is held firmly by the clamp 79 in any esiied position, and I have found in actual practice that the column may be raised a very small fraction of an inch in order to secure this proper focus. Furthermore, it is desirable to make the column 20 separate from the table 13 and the post 11 so that the column can be removed with the post 11 for packing purposes. Inasmuch as the column is to be made removable for transportation, it is obvious that it is a relatively simple matter to provide means for adjustin the column and thus secure the result ca led for.

While I have illustrated details of construction and arrangements of arts which I have found to be particulary desirable and particularly effective in actual practice, I do not wish to be limited to the exact details, as obviously these mi ht be changed in minor respects without departing from the spirit of the invention as defined in the appended claims.

I claim 1. An enlar ing or reducing printer including a tab e, a vertical support operatively mounted in connection with the table for vertical movement with reference thereto, a negative carrying support vertically movable on the vertical member, a lens carrier independently slidable upon the support, a bellows disposed between and connected to the support and carrier iespectively, means automatically decreasing the distance between the lens carrier and the negative support as the negative support is moved away from the table and increasing this distance as the negative support is moved toward the table, and means whereby the vertical member may be vertically shifted with reference to the table.

2. An enlarging and reducing printer including a table having a vertical portion, a column mounted upon the vertical portion of the table for vertical movement toward or from the table, a negative carrying supand means whereby the column may be vertically adjusted with reference to the table 'means for automatically decreasin the disnegativetance between the lens holder an support as the ne ative support is moved away from the tab e and increasing the distance as the negative support is moved toward the table includin a pair of levers pivotally mounted u on t e first named slide and having their ower ends intersecting each other, links pivotally connected to the ends of said levers and extending convergently upward and pivotally connected to said column, and a member having rollers each en aging the inside edge face of one of said fevers, said member being connected to the second named slide.

4. An enlarging or reducing photographic printer including a table, a vertical column mounted upon the table, a slide mounted u on the column, a counter-weight for the slide, a negative support, a lantern carried upon the slide and movable therewith toward and fromthe table, a second slide mounted for vertical movement within the first named slide, a lens carrier mounted on the second named slide, a bellows disposed between and connected to the lens carrier and to the lantern and negative support, means for automatically decreasing the distance between the lens holder and negative support as the negative support is moved away from the table and increasing the distance as the negative support is moved toward the table includin a pair of levers pivotally mounted upon t e first named slide and having their lower ends crossing each other, the inside faces of the lower ends of the levers being concavely curved, links ivotally connected to the outer ends of the overs and extending conver ently upward and being pivotally connects to the upper end of the column, and a member pivotally mounted upon the second named slide and carryi rollers bearing against the inner faces 0 the lower portions of said levers.

5. An enlarging and reducing photographic printer including a table, a vertical column having laterally spaced slideways', a'slide disposed against the face of the column and having portions entering said slideways, and guided thereby, means mounted on the column for ounter-weightward, said levers extending upwardly and divergently, links pivoted to the upper ends of the levers and extending convergeutly upward and being pivotally connected to the column adjacent its upper end, a member mounted upon the second named slide and carrying rollers bearing against the inner edge faces of the two levers, and a lever pivotally mounted upon the second named slide and operatively connected to the lens carrier wherebythe lens carrier may be vertically shifted.

6. An enlarging and reducing photw graphic printer including a. table, a vertical column having laterally spaced slideways, a slide disposed against the face of the column and having portions entering said slideways and guided thereby, means mounted on the column for counter-weighting the slide, the slide being formed with a vertical guideway, a second slide disposed within the vertical guideway and independently movable with relation to the first named slide and carrying guideways adjacent its lower end, a lens carrier mounted between the last named guideways and vertically adjustable the'rebetween, a pair of levers pivoted to the first named slide and having their lower ends extending downward and across each other and over the face of the second named slide, the lower ends of the levers being curved inward, said levers extending upwardly and diver-gently, links pivoted to the upper ends of the levers and extending convergently upward and being pivotally connected to the column adjacent itsupper end, a member mounted upon the second named slide and carrying rollers bearing against the inner edge faces of the two levers, a lever pivotally mounted upon the second named slide and operatively connected to the lens carrier whereby the lens carrier may be vertically shifted and means whereby the column may be vertically shifted with relation to the table and held in its adjusted position.

7. An enlarging and reducing photogriphic printer including a work ta la, a column associated therewith and mounted for vertical adjustment with reference thereto, anegative carrying support mounted ill for vertical movement on the column, a lens carrier independently shiftable vertically upon the support, a bellows disposed between and connected to the support and carrier respectively, means for automatically shifting the lens carrier upon the support as the support is vertically adjusted to secure the proper focusing of the lens on the table, means for raising the column with reference to the table including a fulcrum member mounted upon the table and adapted to act as a fulcrum for a tool, means on the column forming an engaging point for said tool, a rod vertically movable with the column, and a clamp mounted upon the table and adjustable to en age said rod and automatically hold it rom downward movement, said clamp being movable to a position to permit downwar movement of the rod and column.

8. A photographic enlarging and reducing printer including a base portion having a vertically extending member, an upwardly extending member having an upwardly extending pin and the base portion in front of said member having a downwardly extending socket, a column normally resting upon said base portion and carrying at its lower end a downwardly extending pin insertible into said socket, the column having a recess in its rear face into which the vertical member extends and the column having a sleeve fitting said pin at the upper end of said vertical member, the column being formed to provide a medial vertical portion and two side vertical portions defining slideways open upon the front of the column, a slide resting against the face of the column and having guides projecting into said slideways, a counter-weight moving in the recessed rear face of the column and having a cable passing over the top of the column and operatively engaging said slide, there being pulleys in the top of the column over which said cable passes, the base of said slide being formed with a vertical guideway, a second named slide disposed in said guideway for vertical movement with reference to the first named slide, a lens support slidably mounted upon the second named slide for vertical movement, means mounted upon the second named slide and connected to the lens support whereby the lens support may be vertically moved with reference to the second named slide, a lantern, a negative support mounted upon the first named slide, a bellows connecting the lens support and said negative and lantern support, means for automatically focusin the lens as the first named slide is move toward or from the table comprising levers pivoted upon the first named slide at each side thereof, said levers extendin downward and crossing each other an havin their inner faces slightly curved, a T-shaped member pivotally mounted upon the second named slide and having rollers at the ends of the cross arm of the T restin against the edge faces of said levers, and inks pivotally connected to the upper ends of said levers and pivotally connected to the upper end of the column.

9. A photographic enlarging and reducing printer including a paper support, a negative carrier movable toward or away from the paper support, a lens carrier independently movable toward or from the paper carrier, a bellows disposed between and connected to the negative support and the lens carrier respectively, means automatically decreasing the distance between the lens carrier and the negative support as the negative support is moved away from the paper support and increasing the distance as the lens carrier is moved toward the paper support to thereby automatically focus the lens upon the paper support at all times, and independent means for bodily adjusting the paper support and the negative carrier toward or from each other.

10. A photographic enlarging and reducing printer includin a sensitized paper support, a longitudinal y extending member, a negative carrying support longitudinally shifta-ble on the longitudinal member, a slide mounted for longitudinal movement upon the negative support, a lens carrier mounted upon said slide, a bellows disposed between and connected to the negative support and the lens carrier respectively, means for automatically decreasing the distance between the lens carrier and the negative support as the negative support is moved away from the sensitized paper support and automatically increasing this distance as the negative support is moved toward the paper support, and independent manually operable means for increasing or decreasing the distance between the negative support and the sensitized paper support without affecting the distance between the lens carrier and the'negative support.

In testimony whereof I hereunto atlix my signature.

ALFRED M. THOMAS. 

